Evolution

A better understanding of human smell is emerging as scientists interrogate its fundamental elements: the odor molecules that enter your nose and the individual neurons that translate them into perception in your brain.

Scientists reconstructed 500 million years of evolutionary history to reveal which came first: colorful signals or the color vision needed to see them.

Studies of neural metabolism reveal our brain’s effort to keep us alive and the evolutionary constraints that sculpted our most complex organ.

Complex neural pathways likely arose independently in birds and mammals, suggesting that vertebrates evolved intelligence multiple times.

Evolution was fueled by endosymbiosis, cellular alliances in which one microbe makes a permanent home inside another. For the first time, biologists made it happen in the lab.

Biologists used artificial intelligence to make discoveries about molecules and the brain, and overturned long-held assumptions about the immune system and RNA.

We often consider spoken language to be a feature that distinguishes humans from other forms of animal life. Brain research, however, suggests that other creatures — including certain birds — share some of our neural circuitry related to language. In this episode, co-host Janna Levin explores the origins and underlying mechanisms of human speech and birdsong with neurobiologist and geneticist Erich Jarvis.

The clearest picture yet of our “last universal common ancestor” suggests it was a relatively complex organism living 4.2 billion years ago, a time long considered too harsh for life to flourish.

All modern multicellular life — all life that any of us regularly see — is made of cells with a knack for compartmentalization. Recent discoveries are revealing how the first eukaryote got its start.